Many miniaturized electronic devices, such as cellular phones, smart cards, personal digital assistants (PDAs), electronic games, and/or electronic organizers have built-in memory associated with the devices. In the past, the amount of memory associated with the electronic devices has been relatively small. However, the amount of memory associated with these electronic devices has steadily increased.
In particular, flash memory can be employed in these types of electronic devices. Flash memory is a type of electronic memory media that can be rewritten and can retain content without consumption of power. Flash memory has become popular, at least in part, because it combines the advantages of the high density and low cost of erasable programmable read only memory (EPROM) with the electrical erasability of electronically erasable programmable read only memory (EEPROM). Flash memory is non-volatile; it can be rewritten and can hold its content without power. It can be used in many portable electronic products, such as cell phones, portable computers, voice recorders, thumbnail drives and the like, as well as in many larger electronic systems, such as cars, planes, industrial control systems, etc. The fact that flash memory can be rewritten as well as its retention of data without a power source, small size and light weight have all combined to make flash memory devices useful and popular means for transporting and maintaining data.
Typically, programming data to the memory contained in the electronic devices has been performed using a serial interface associated with an external source such as a card reader or host computer. The external source can also provide the power associated with the programming operation to the electronic device. Conventionally, the transmit and receive clock used for transferring the data over the serial link has operated at the same frequency such that data programmed to the electronic device is transmitted at the same speed as data read from the electronic device.
However, with the advent of smaller memory that can be fabricated on the electronic devices and the relative low cost of the memory, the size of the memory associated with the electronic devices have grown substantially. As a result, the amount of information that can be stored in such electronic devices has grown, and there is an ever increasing demand for storing greater amounts of information in electronic devices, such as portable electronic devices (e.g., smart card, cellular phone, etc.). Based on a given clock rate, as the amount of data to be programmed increases, the amount time to accomplish such programming operation can also increase. While the amount of data programmed to memory in electronic devices can be a relatively large amount, the amount of data typically read from the memory is relatively small.
It is desirable to be able to transmit and program data to the memory of an electronic device at increased speeds as this can result in higher productivity and/or lower manufacturing cost due in part to the decreased amount of programming time associated with programming data to memory in such electronic devices.